Loom shuttle having installed or attached structures liable to be subjected to shock



Feb. 8, 1966 H. KLOCKER ETAL 3,233,635

LOOM SHUTTLE mvme INSTALLED OR ACHED STRUCTURES LIABLE TO BE SUBJEGTED snocx Filed May 29, 1963 4 Sheets-Sheet 1 mars M 1 1966 H. KLOCKER ETAL 3,

LOOM SHUTTLE HAVING INSTALLED 0R ATTACHED STRUCTURES LIABLE TO BE SUBJECTED T0 SHOCK Filed May 29, 1963 4 Sheets-Sheet 2 [7n vea /0r.-

H. KLOCKER ETAL 3,233,635

Feb. 8, 1966 LOOM SHUTTLE HAVING INSTALLED 0R ATTACHED STRUCTURES LIABLE TO BE SUBJEC'IED TO SHOCK 4 Sheets-Sheet 5 Filed May 29, 1963 1966 H. KLCICKER ETAL 3, 3

LOOM SHUTTLE HAVING INSTALLED OR ATTACHED STRUCTURES LIABLE To BE SUBJECTED TO SHOCK Filed May 29, 1963 4 Sheets-Sheet 4 I Jng nzor:

I I I United States Patent O K 4s,s01

14 (Ilaims. or. 139-207 As a result of the constant increase in the speed of loom shuttles, the danger of damage to the structures usually installed in or attached to suchloom shuttles is increasing to. such an extent that special steps must be taken to reduce the resulting stresses. The solutions which have been proposed are mutually contradictory in their approach. If resiliently yielding parts, for instance materials having such properties, are provided between the installed or attached ;structures and the rigid parts of the loom shuttle, the quality of the joint between the loom shuttle .and these installed or attached structures will be reduced. On 'the other hand,ywhen it is desired to provide a joint having the required strength, a corresponding prestressingof these resiliently yielding parts or materials is required so that their hardness, and consequently the shock stresses are increased.

;It is an object of the present invention to avoid these undesirableeltects. Loo-m shuttles embodying the invention and havinginstalled and/or attached structures which are liablevto be subjected to shock are characterized in that installed or attached structures of the loom shuttle consist of at least two members which form a common installed or attached unit, one of said members being rigid whereas the other is resiliently yieldable. It is particularly suitable to form the installed or attached structures of three members forming a common installed r attached unit, the intermediate member of the unit consisting preferably of resiliently yielding materials having a high resilience, such as rubber elastomers or plastics, e.g., ethylene glycol polyesters or adipic acid, 1,2-propylene glycol polyesters or the like, whereas the outer members consist suitably of hard materials, such as metals (steel), which are bonded to the inter-mediate member by vulcanizing, polymerizing or other methods to form said units. This design renders the resiliently yielding properties of these materials fully effective whereas the strength of the joint is not altered at all. This will be explained in more detail with reference to the loom shuttle tip, which is particularly liable to be subjected to shock. According to the invention a loom shuttle tip-consisting of a unit which precedes the loom shuttle body-consists of three members, a front member which tapers to a point, succeeded toward the loom shuttle body by an intermediate member having resiliently yielding proper-ties, and an end member which provides for the transition and connection to the loom shuttle body. As a result of this design of the loom shuttle tip the front member, which is liable to be subjected to shock, is perfectly resiliently cushioned because it is succeeded by the intermediate member, which has the necessary shock-absorbing proper ties. This intermediate member may be firmly connected to the end member, which can in turn be connected to the loom shuttle body as firmly as is required for a reliable absorption and transmission of the forces which are created by the shock.

The resiliently yielding members may be designed in various ways, one of which has already been mentioned and resides in the provision of resiliently yielding materials in the form of rubber, elastomers or plastics. A

second possibility resides in that the resiliently yielding members of the installed and/or attache-d structures are formed from hard materials having resilient properties, for instance in the form of annular springs, disc springs, helical springs, spiral springs, leaf springs or the like. Both features may be combined by providing hand materials of resilient configuration as metallic inserts in the elastically yielding material. In the two last-mentioned cases it is suitable to provide stops for limiting the movement of the hard material, e.g. the spring, so that a rigid -=connection will be provided when the resilient absorption of a major part of the shock has resulted in a predetermined spring displacement, whereas the stops serve to prevent an overstraining of the elastically yielding material.

In some cases it may be suitable to use the yielding resilient material as a covering on parts which adjoin said material in order to camouflage such parts, protect them from stresses which may occur on their outside, or provide transitions for which latter the resiliently yielding material is particularly suitable.

It has already been pointed out that it may be suitable to provide hard materials of resilient configuration as inserts in the elastically yielding material. However, the invention is not restricted to this arrangement. It is also possible to support a member which consists at least partly of resiliently yielding materials by means of members consisting of hard materials having resilient properties on a member which consists of rigid materials. In this way the member which consists of resiliently yielding materials can be protected to a large extent from the direct effects of a shock because the last mentioned members take up a major part ofthe shock energy and dissipate it by deformation and transformation into heat. This enables the member consisting of resiliently yielding mate rial to take up shocks to such an extent that the permissible number of load cycles corresponds approximately to that which occurs during the usual life of a loom shuttle.

There is a large number of possibilities for carrying the invention int-o cite-ct. If the above-mentioned proposal is followed to provide loo-m shuttles with installed or attached structures consisting of three members, an intermediate one of which consists preferably of resiliently yielding materials Whereas the end members consist of hard materials, such as metals, it will be suitable to arrange the element consisting of hard materials having resilient properties, for instance steel springs, between the members consisting of resilient materials and the adjoining member of rigid materials, respectiVely and in such a manner that the elements consisting of hard ma terials having resilient properties at least partly support the member consisting of resilient materials. If the elements consist of disc springs it will be particularly advantageous to reliably hold them as required and in addition to conceal them entirely from the outside. The same applies if the elements consist of annular springs.

Those elements which consist of hard materials having resilient properties must be centered and secured in the correct position. This is suitably effected by means of a member which consists of rigid materials, the arrangement being preferably such that this member and the element or elements interlock in the direction of shock; this can be achieved in various ways, for instance in that a 'pinlike part of the loom shuttle tip consisting of rigid materials is surrounded by an annular member of resiliently yielding materials and has a centering extension, for instance in the form of a pin smaller in diameter, which is suitably received in an opening of the spring element in such a manner that the shoulder formed between the two pins is in positive engagement with the element in the direction of shock transmittal. As a result, shock forces will be transmitted only between members of rigid materials suitable for taking up the shock forces, and the abovementioned annular member of resiliently yielding materials need only follow the resilient displacement of the spring elements so that the annular member is largely relieved of the above-mentioned forces. The spring discs, or the rings of an annular spring, may be so accommodated in the opening of a member consisting of rigid materials that in their rest position they protrude beyond this member and engage the adjacent member, whereas they will lie entirely within the opening when they are under the action of shock forces. This enables support of the member consisting of resiliently yielding materials on a large surface and edges or pointed parts tending to disintegrate the material are thus eliminated, so that a beneficial effect on the life of the member of resiliently yielding materials is obtained. If the opening for the elements is provided in a disc serving to accommodate the elements and adjoined in the direction of the loom shuttle body first by a member of rigid materials forming the tip of the loom shuttle body and then by an annular member of resiliently yielding materials surrounding the pinlike projection of the loom shuttle tip, a compact arrangement of these members will be obtained and these members will be accommodated without diificulty within the restricted space of the loom shuttle tip. Since owing to the continual resilient displacement of the spring elements any occluded air would be subjected to a steep temperature rise whereby the life of the members consisting of resiliently yielding materials could be adversely affected, the space for accommodating the spring elements is suitably vented.

When it is desired to form the described members of the loom shuttle tip as a physically coherent unit, a special method must be employed to ensure that the function assigned to the members is not adversely affected or even completely negated. The method resides in that the assembly of the members into a common unit is effected when the elements have performed their resilient displacement, for instance when disc springs have been compressed to form perfectly fiat discs. Only when this condition has been reached is the member consisting of resiliently yielding materials placed into position, for instance by casting, injecting, pressing or the like; this is followed by vulcanizing or polymerizing steps which result in a proper connection between the compressed members.

The metal parts of a loom shuttle do not only include the loom shuttle tip but also the so-called gripper spring device, which receives the butt end of the bobbin so as to hold the entire filling bobbin in the trough cavity of the shuttle. When the shuttle is reversed, this gripper spring device consisting generally of a gripping spring and a bobbin directing grip strap, is subjected to extremely high stresses by the resulting retardation and acceleration of masses, particularly because the accommodation of the gripper spring device in a space which is necessarily very small involves the formation of very sharp bends having small radii of curvature. Moreover, in automatic bobbin-changing looms transfer of a filling bobbin to an eccentric position in a shuttle having a rigidly located gripper spring will cause one jaw of the gripper spring to be bent beyond its elastic deformation. This results in breakage of parts of the gripper spring device after a relatively small number of reversals so that the problem arises to so design this gripper spring device that the shocks which may arise are resiliently and gently absorbed. Also, the previous design of gripper spring devices required the use of at least two fixing screw bolts which added to the non-cushioned mass. In addition, there were weakened portions in the gripper spring device itself and, above all, in the loom shuttle body, and these weakened portions resulted in a considerable reduction in the strength of both parts. Because the gripper spring is formed on its confronting inner boundary surfaces with grooves formed as segments of an ellipsoid and serving to receive retaining rings provided on the butt end of the filling bobbin, the need for achieving an exact coincidence of the positions of the retaining rings and grooves during the automatic change of the filling bobbin requires that the distance from the butt end of the bobbin to the bobbin directing grip strap or bobbin cover and the opening of the gripper spring is absolutely constant. This is rather difficult in practice because the position of the gripper spring device depends on the openings formed in the loom shuttle body for receiving the above-mentioned connecting bolts, particularly because the position of the bobbin directing grip strap determines the position of the gripper spring. The previously common gripper spring devices are unsatisfactory also from this aspect.

These disadvantages will be avoided if the loom shuttle is designed according to the invention.

This design is characterized according to the invention in that the gripper spring device of the loom shuttle consists of a unit of the type, which comprises rigid and resiliently yielding members.

This results in a number of advantages which reside mainly in that the resiliently yielding members of the unit protect the rigid members from the effects of shocks occurring when the loom shuttle is reversed, the resiliently yielding members damping the effects of the shock on the rigid members and transforming the shock energy into work of deformation. As will be explained in detail hereinafter, the novel design of the gripper spring device requires only a single fixing bolt for fixing the device to the loom shuttle body so that the number of stressed members is reduced by half and the weakening of the loom shuttle body is eliminated, the latter having been previously caused by the need for forming the loom shuttle body with special openings for receiving or accommodating the second fixing bolt. The fact that the gripper spring and the bobbin directing grip strap now form a single unit with the resiliently yielding member ensures without difficulty a constant distance from the grooves formed in the gripper spring for receiving the butt end of the bobbin and the bobbin directing grip strap, where as a careful relative arrangement of these two parts was previously required to keep this distance constant. Because a single common part can be readily accommodated in the loom shuttle body in a predetermined position, it has been possible to eliminate a source of error, the avoidance of which involved great difficulties before.

If the unit consisting of the gripper spring and the bobbin directing grip strap is rotatable and adjustable as a whole about an axis extending transversely and preferably at right angles to the shuttle race or the bottom of the loorn shuttle and if the unit can be fixed in its adjusted position, further advantages will be obtained, which reside mainly in that the high stresses on the material of the holder are eliminated, whereas the stresses were previously inevitable if the filling bobbins were transferred into an eccentric position and also if the bobbin holder was inherently in a wrong position in the loom shuttle body. The above-mentioned adjustment enables an elimination of detrimental effects of the transfer into an eccentric position so that overstressing of the material is eliminated, a factor which caused a large number of breakages of the gripper spring device consisting generally of a gripper spring and a bobbin directing grip strap.

Special advantages will be obtained owing to the fact that bodies or layers of resiliently yielding materials may be disposed between the loom shuttle and the holder for the filling bobbin so that the stresses due to shocks arising when the shuttle is being propelled or braked are substantially reduced.

It is further characteristic of the invention that only the bobbin directing grip strap is rigidly connected to the loom shuttle whereas the gripper spring is movable relative to the bobbin directing grip strap within certain limits, owing to the provision of members consisting of resiliently, yielding bodies or layers, said limits being restricted only by the resilience of said bodies orlayers. As a result, the gripper spring can yield as a whole when the filling bobbin is transferred into an eccentric position so that bending of only one limb of the spring to the point of fracture is avoided. In other Words, the gripper spring is pivotally movable relative to the bobbin directing grip strap and is nevertheless firmly held by the rubber-metal bond.

A particularly suitable design will be obtained if the gripper spring and bobbin directing gripstrap constituting the gripper spring device of a filling bobbin holder comprise a connecting member of resiliently yielding materials, which entirely or substantially'fills the space defined by the bobbin directing grip strap so that the protruding beam portions can be deflected without restriction. This affords a simple possibility of combining said members in common installed unit, which is formed by inseparably bonding the connecting member to the gripper spring. or bobbin directing grip strap by vulcanizing, polymerizing or by other methods. Whereas such a connection is desirable according to the present invention, it is not essential because a gripper spring device designed according to the invention will afford the above-mentioned advantages even when the beam consisting of resilient materials is connected byother methods to the bobbin directing grip strap and the gripper spring in such a manner that a common :unit is obtained. This may be accomplished, for instance, by mechanically clamping the members together.

Further advantages will be obtained if a spacer tube is arranged between the limbs ofthe bobbin directing grip strap extending parallel to the bottom of the shuttle and the connecting bolt for adjustably fixing the gripper spring device in the loom shuttle body is accommodated in the cavity of this tube. The spacer tube enables a tightening of the connecting bolt with any desired force without exerting forces on the connecting member, which-is not designed for taking up such forces or the free resilience of which would be adversely affected by such forces. For the same reason the height of the gripper spring measured in the direction of the connecting bolt is suitably smaller than the spacing between the limbs of the bobbin directinggrip strap, measured in the same direction. The resulting spaces may accommodate portions of the connecting member consisting of resiliently yielding materials so that metallic contact between the gripper spring and the bobbin directing grip strap is eliminated. Owing to the continually changing relative position of the two parts, such metallic contact would cause wear and an unnecessary reduction of the resilience of the resilient material. In other words, the spacer tube is longer than corresponds to the height of the gripper spring ,so that forces exerted on the installed unit during the fixation thereof will not vary the resilience of the resilient members of the installed unit and will increase the hardness of the resulting spring.

If at least that boundary surface ofthe bobbin directing grip strap which faces the loom shuttle bottom is covered with resiliently yielding materials ,or if the bobbin directing grip strap is designed to form a carrier of bodies consisting of these materials, for instance, in the form of cover plates, relatively small forces derived from tightening of the connecting bolt will be sufii-cient for adequately retaining the gripper spring device in position on the loom shuttle body because high frictional forces will be in effect.

If the bobbin directing grip strap, gripper spring and connecting member are combined in a unit, it will be de sirable that only those boundary faces of the connecting member which face and/or are remote from the shuttle bottom are connected to the limbs of the bobbin directing grip strap by means of layers which are made and bonded by vulcanizing and polymerizing. The other boundary layers are preferably free of such bonding layers to avoid an unnecessary reduction in the resilience of the beamlike connecting member of resiliently yielding materials. Besides, the bonding layers may be entirely omitted since the bobbin directing grip strap can hold the connecting member in a strictly mechanical manner by surrounding it in the form of a closed ring and because the abovementioned connecting bolt is provided, which retains the parts in their relative position without the need for combining them in a unit. If the connecting member is slightly oversize, the bobbing directing grip strap can set up in the connecting member an initial stress, which may be desirable under certain circumstances for increasing the reliability of the connection.

If the free limbs of the gripper spring are covered with resiliently yielding materials or are designed to form carriers of pads consisting of such materials, it is no longer necessary to set the butt end of the bobbin with annular members which are received by correspondingly shaped grooves in the gripper spring. If such layers or pads of resiliently yielding materials are interposed, the frictional forces effective between the butt end of the bobbin and the gripper spring will be entirely sufficient to hold the filling bobbin in the required manner if the gripped portion of the butt end of the bobbin is given, for instance, a frusto-conical shape. Besides, the shock stresses which arise when the shuttle is being driven or braked will already be resiliently taken up and damped at this point so that those members of the gripper spring device which serve forfixing the same in position in the shuttle body will be relieved from the shocks.

What has been said for bobbin holding means in the form of a gripper spring device applies analogously to dilferent forms of filling bobbin holders.

Preferred resiliently yielding materials are those which exert large restoring forces, such as certain rubbers or plastics, for instance, ethylene glycol polyesters or adipic acid 1,2 propylene glycol polyesters. All these substances are capable of firmly adhering to metal parts by vulcanizing or polymerizing so that the members thus bonded together form a physically coherent unit.

If that limb of thebobbin directing grip strap which is disposed opposite a base portion of the bobbin directing grip strap is flush with the apex of the single bend in the gripper spring of U-shaped cross-section, that portion of the connecting member which adjoins the bend of the gripper spring and that part of the base portion of the bobbin directing grip strap which protrudes beyond the bend of the gripper spring, may entirely consist of resiliently yielding materials so that the installed unit is cushioned as a whole against the single connecting bolt by which it is fixed to the loom shuttle body and. which extends through a transverse opening of this connecting member. As a result, the loom shuttle body will transmit the retardations and accelerations occurring when the direction of the movement of the loom shuttle body is changed, will only be transmitted from the latter to the gripper spring device by members which consist entirely of resiliently yielding materialsso that the desired, full cushioning and protection of the gripper spring device against shocklike stresses will be obtained as is the object of the invention.

Another metallic structure installed in such a loom shuttle is the so-called threading device. A resiliently yielding arrangement of this device is dilficult to achieve unless the following measures are adopted in a further development of the invention.

If a holder of a resiliently yielding material and provided on one side with a threading device and on the other side with rigid fixing means for the assembly, is designed as a unit in which the holder forms the intermediate member and the threading device and the holder are open to the air, except for the interface formed by the fixing means, the threading device may be mounted so that it can swing freely without impairing the threading operation.

The holder consists suitably of a base plate of an installed unit forming the assembly.

A simple and reliable fixation of the installed device will be obtained if the holding means consist of a metal plate bonded to the holder by vulcanizing or polymerizing and of a stud which carries this plate and is mounted in a wall of the loom shuttle. The stud may be additionally locked in position. It may have self-tapping screw threads, which ensure a firm mounting of the stud in the loom shuttle body. If a screw-threaded extension of the stud can be received by the metal plate, this screwthreaded extension may protrude beyond that portion of the stud which is accommodated in the loom shuttle body to provide between the holder of resiliently yielding material and the loom shuttle body the clearance required to ensure that the threading device can swing freely.

The drawing shows a number of illustrative embodiments in partly diagrammatic views. Specifically, FIG. 1 is a view partly in section and partly in elevation and shows a loom shuttle tip embodying the invention. FIG. 2 shows the loom shuttle tip according to FIG. 1 installed into the body of the loom shuttle. FIG. 3 shows a modification of the embodiment shown in FIGS. 1 and 2. FIG. 4 shows another modification. FIG. 5 is a sectional view similar to FIGS. 1 to 4 and shows another embodiment. FIG. 6 is a vertical longitudinal sectional view taken on line VIVI of FIG. 7 and showing a gripper spring device forming in accordance with the invention a single unit to be installed whereas FIG. 7 is a top plan view showing the arrangement of FIG. 6 as viewed in the direction of the arrow VII. FIG. 8 is a sectional view taken on line VIII-VIII of FIG. 9 and shows the gripper spring device of FIG. 6 installed in the loom shuttle body whereas FIG. 9 is a top plan view showing the loom shuttle of FIG. 8. FIG. 10 is a vertical transverse sectional view taken through the butt end of the bobbin and showing a modification of the gripper spring device of FIGS. 6 to 9. FIG. 11 is an elevational view of the embodiment shown in FIG. 10 and includes a partial section taken on the line XI-XI of that figure. Finally, FIG. 12 is a longitudinal sectional view taken through a wall of the loom shuttle body and showing the arrangement of a threading device embodying the invention.

It is apparent from FIG. 1 that the loom shuttle tip comprises a front member 1, which may consist of steel or other hard materials. The intermediate member 2 consists of resiliently yielding materials having a high resilience or restoring power and is bonded to the front member 1 by v-ulcanizing or polymerizing. The resiliently yielding materials may consist of elastomers or natural or artificial rubber or of plastics such as ethylene glycol polyesters or adipic acid 1,2-propylene glycol polyesters, to mention some particularly suitable materials. The polymerized layer 3 provides a firm, inseparable bond between the parts 1, 2. A second layer of bonding polymers is indicated at 4 and serves for bonding another metal member 5 to the intermediate member 2. The bond 2 is also firm and inseparable. The metal part 5 consists generally of steel and forms the end member of the tip; it carries the pinlike extension 6, which is formed with grooves 7. The front member 1 carries also a pinlike extension 8, which has such a length that the end face of the pin 8 will engage the metal member 5 when the intermediate member 2 has been subjected to the largest deformation possible without danger of destruction or damage.

Hence, the parts 1, 2, 5 including the bonding layers 3, 4 form a unit known as a metal-clad rubber block. In this case the layers 3, 4 consist of rubber hydrochloride. The member 1 receives the shock, which is damped by member 2, and the member 5, 6 provides for a rigid connection between the entire unit and the loom shuttle body 9.

FIG. 2 shows the loom shuttle tip according to FIG. 1 installed in the body 9 of the loom shuttle. The fixing extension 6, 7 is received in an opening 10 of the shuttle body, the opening being bounded by a circumferential wall, and suitable connecting means being provided to hold the whole structure together.

It is obvious that the intermediate member 2 can be given any desired resilience by a proper selection of the material. For the same purpose the intermediate member 2 may incorporate or be replaced by resilient metal parts in the form of annular springs, disc springs, helical springs, spiral springs or leaf springs, as has already been mentioned.

In the illustrative embodiment shown in FIG. 3 the metal or steel member 5 is reduced in diameter so that the lateral boundary surface of the part 5, which boundary surface has the shape of a cylindrical ring, is covered at 11 by the resiliently yielding material of the intermediate member 2. The metal member 5 is adjoined toward the loom shuttle body 9 by another member 12 consisting of the material of the intermediate member 2 so that a snug contact between the loom shuttle tip and the loom shuttle body is ensured independently of the surface finish of the end face of the loom shuttle body 9. Numeral 4 designates layers providing a firm, inseparable bond. Such layers may also be provided on the other boundary surfaces of the member 5 for holding the part 12, which forms a separate washer consisting of the material of the intermediate member 2, whereas in the example shown in the drawing the plate 5 is held in position by expanding the opening 13.

In the illustrative embodiment shown in FIG. 4, the usual washer 14 of vulcanized fiber is applied to the extension 6 of the end member 5. Layers 4 of rubber hydrochloride provide a finm and inseparable bond between the plate 5 and the intermediate member 2.

FIG. 5 shows another illustrative embodiment. 1 is again the loom shuttle tip proper consisting of steel and adjoined by further members combined in a unit therewith and distinguished from the loom shuttle tip proper by being described as a loom shuttle tip assembly. These parts will be described more fully in detail hereinafter. The loom shuttle tip proper 1 of steel has again a first pin-shaped extension 8, which is followed by another pin-shaped centering extension 15, somewhat reduced in diameter for centering the spring element. This second centering extension is not necessary because the loom shuttle tip assembly is designed so that the spring element can be centered without need for special centering means. This will be explained hereinafter. In the embodiment shown the centering extension 15, which like the parts 1 and 2 consists of steel, is disposed in the central opening of two disc springs 16 and 17 forming the spring element. The disc springs 16 and 17 are somewhat dished, in usual manner, to engage the annular shoulder 18, which is formed by the pins 8 and 15. The disc springs 16, 17 are accommodated in a recess 19 of a second steel member, which consists primarily of the disc 5 and the attached fixing pin 6, which latter has been formed with the circumferential fixing grooves '7. The pin-shaped extension 6 of the disc 5 is received by the bore 10 of the loom shuttle body 9. The pin 6 has a through bore 20, through which the chamber 21. formed by the recess 19 communicates with the cavity 22 defined by the bore 11) and further through the transverse with the atmosphere through the transverse bore 23. Hence, the enclosed air cannot be compressed and heated by the move- 9 ment of the disc springs 16, 17, so that there will be no adverse effects on the resiliently yielding material forming an annular member 2, which surrounds the pin 8 and the outside periphery of i which conforms to the shape of the loom shuttle body 9.

The disc springs 16, 17 need not be centered by the centering extension 15 of the loom shuttle tip proper 1 because the recess 19 in the disc 5 can serve to center the disc springs.

The operation of the illustrated device is as follows:

A shock exerted on the loom shuttle tip 1 proper, to which the steel pins 8, are connected, will primarily be taken up by the disc springs 16, 17 because the annular shoulder 18 formed by the parts 8, 15 directly engages the disc spring 16 facing the loom shuttle tip proper 1. The disc springs are dimensioned so that they cannot normally contact the bottom surface 24 of the recess 19in the disc 5. Because the shock causes a change in the relative position of the confronting boundary surfaces 3 and 4 of the loom shuttle tip proper 1 and the disc 5, respectively the part 2, which consists of resiliently yielding materials and which may be referred to as a spring member takes up only that part of the shock which has not been dissipated in the disc springs 8; 15. The forces can thus be considered to be divided into a major first part taken up by the disc springs 8, 15 and a balance taken up by the spring member 2. This results in the expected relief of the spring member 2 so that the same may consist of available materials which will not be adversely affected by a number of load cycles corresponding to that which the loom shuttle as such will withstand.

In the manufacture of the loom shuttle tip, the parts 1, 15, on the one hand, and 5, 6, on the other hand, are compressed together with the inserted springs 16, 17 in a gripping device so that the disc spring 17 contacts the bottom surface 24 of the recess 19. In this condition of the loom shuttle tip, the resiliently yielding material of the annular spring member 5 is introduced in the usual manner, for instance, by injecting, casting or pressing, and at the same time or thereafter the steps are performed which cause the parts 1, 8 and, if desired, 15, 2, 5 and 6, to form a unit. The loom shuttle tip is then removed from the gripping device and is secured in usual manner to' the loom'shuttle body 9.

Referring to the illustrative embodiment shown in FIGS. 6-9, FIGS. 6 and 7' show primarily the known parts of a gripper spring device, which consist of rigid materials, such as spring steel. These parts include the gripper spring 26 and the cover plate 25. FIG. 7 shows in a top plan view of the gripper spring 26 that the same consists of the two limbs 27 and 28 and a single bend 29, which connects the two limbs 27 and 28 so that the gripper spring is U-shaped in top plan view and in crosssection. FIGS. 6 and 7 show also oval grooves or recesses 30 formed in the spring limbs 27 and 28 for receiving the retaining rings, not shown, of the butt end of the bobbin when there is an exchange of filling bobbins. The butt end of the bobbin is not shown either. These grooves have the three-dimensional shapes of truncated hollow ellipsoids.

The cover plate 25 comprises the base limb 32 facing the shuttle bottom, the web portions 33, 34 and the top limb 35. The base limb 32 and the top limb 35 are covered with rubber surface layers 36, 37 so that when the gripper-spring device which includes the cover plate 25, is mounted in the body of the loom shuttle as shown in FIG. 8, these rubber layers contact the adjacent portions of the shuttle body.

The damping member 31 comprises an intermediate portion 33, which fills the cavity defined by the cover plate portions 32, 33, 34, 35 and by the bend 29 of the gripper spring 26. The rubber block 38 is extended beyond the width 39 of the web portions 33, 34 to form protruding portions 40, 41, the ends of which are bonded by vulcanizing or polymerizing to the limbs 27, 28 and to the end portions of the bend 29 of the gripper spring 26 so that the above-mentioned unit is obtained. On the other hand, there are no bonding layers formed by vulcanizing or polymerizing between the intermediate portion 38 of rubber and the web portions 33, 34 in the width 39 so that the mass of the rubber core 38 participates in damping and cushioning the shocks. This would not be the case if there were bonding layers in these areas because the portions 33 34, 38' owing to their material connection would then have the same resilient and damping properties as a pieceof rigidma'terial.

The limbs 32, 35 of the cover plate 25 extend parallel to the bottom of the loom shuttle and are held in their relative position by the spacer bushing 42, which adjoins corresponding openings in the limbs 32, 35 and the rubber coverings 36, 37. Portions 43and 44 of the intermediate rubber portion 38 of rubber block 38, 40, 41 are disposed between the bend 29 of the gripper spring 26 and the limps 32, 35 of the cover plate 25 parallel to the bottom of the, loom shuttle and enable damped and cushioned. relative movements of parts 25, 26 in the direction of the spacer bushing 42 transversely or at. right angles to the shuttle race or the shuttlebottom.

FIGS. 8 and.9 illustrate the device in installed position in the body 45 of the loom shuttle,.the tip 46 of which is suitably designed according to FIGS. 1 to 5.

When the device has been installed, a connecting bolt 47 extends through the spacer bushing 42 which connects the limbs 32, 35 of the cover plate 25 with the rubber block 38 to which the gripper spring 26 is secured. Bolt 47 engages a tapped bushing 48 which receives the shank formed with screw threads 49; A lock washer 50 abuts the layer 37 covering limb 35 and is compressed there against by the head of the bolt 47 to hold the connecting bolt in its installed position. The spacer bushing 42 has such a height that the base limb 32 of the installed unit cannot bear on the upper annular surface of the tapped bushing 48 because this would eliminate or at least adversely affect the resilience of the rubber layer 36. In other words, bushing 42 projects somewhat beyond the limb 32 and its rubber layer 36 and itself engages the tapped bushing 48.

FIGS. 10 and 11 show a gripper spring 26 which is modified relative to FIGS. 6 to 9. The limbs.27,. 28 of the gripper spring 26 in this embodiment are designed as carriers of rubber pads 51, 52,.which may be replaced by rubber layers formed on and bonded to the limbs 27, 28 by vulcanizing or polymerizing; The pads 51, 52 receive the butt end of a spindle53, which carries the filling bobbin. This butt end comprises a pair of oppositely frustoconical portions 54, 55 and a cylindrical intermediate portion 56 so that it need not be provided with metal reinforcements, which mainly consist of applied rings and enable the filling bobbin to be connected to the gripper spring device in the direction of propulsion of the shuttle partly by frictional contact and partly by interengagement with the grooves 30. The elimination of the metal fittings reduces the weights and consequently the masses and inertia forces. Additionally, other disadvantages of the metal fittings are eliminated. Nevertheless, even with the metal fittings omitted the connection which in the instant embodiment also depends partly on frictional contact and partly on interengagement is sufiicient for reliably holding the filling bobbin in position in the loom shuttle.

As is apparent from the top plan view shown in FIG. 9, the design of the gripper spring device according to the invention results in a considerable reduction of the installed length. Compact, strong transitions are particularly obtained at point 57 between the shuttle walls 59, 6t? defining the trough cavity 58 for the filling bobbin and the front portion 61 of the loom shuttle so that the resistance to buckling of the shuttle body is substantially increased as well as its rigidity. Further advantages reside in that the accelerating and retarding forces no longer act on the gripper spring arrangement and the filling bobbin directly but are greatly damped and reduced in magnitude. This will reduce the stressing of the gripper spring device as well as of the yarn so that the tendency of the yarn to slough is reduced. Breakage of the gripper springs no longer occurs whereas it occurs often when the arrangement according to the invention is not adopted. It is no longer possible to transfer the filling bobbin into an eccentric position because the gripper spring device can yield. Besides, this device can be adjusted so exactly that this will prevent any transfer of the bobbin into an eccentric position. The connecting bolt 47 is readily accessible so that it can be adjusted without need for removing the shuttle from the race. A wrong installation, as was frequently observed before, is precluded.

FIG. 12 is a longitudinal sectional view showing the threading device and that portion of the loom shuttle which accommodates the threading device and illustrates by way of example another embodiment of the invention.

In this figure, the threading device 63 is connected to the base plate 64 of resiliently yielding material to form a unit therewith. For this purpose, the base plate 64 is bonded to the threading device 63 by vulcanizing or polymerizing throughout its boundary face 65 confronting the threading device 63. The base plate 64 has further bonded to it by vulcanizing or polymerizing the metal plate 66, which has a tapped opening receiving the screwthreaded extension 67 of the screw-threaded stud 68, which is provided at 69 with a transverse slot enabling adjustment of the stud 68 when the same is positioned in a suitable opening in the loom shuttle body 9. A nut 71 guided on the screw threads 70 of the stud 68 serves for locking the stud 63 in its final position, in which the screw-threaded extension 6'7 protrudes beyond that portion of the stud 68 which is accommodated in the loom shuttle body 9 so that air-filled gaps 74 result between the portions 63, 64, 66 and the opposite boundary surfaces 72 of the opening 73 formed in the loom shuttle body 9 and serving to accommodate the portions 63, 64, 66. Hence, the threading device 63 can swing freely in all directions with the required degree of freedom without restriction by the adjacent loom shuttle body 9. Any shocks which occur will be damped in the base plate 64 consisting of rubber or rubberlike plastics so that the life of the threading device 63 is no longer adversely affected by the absorption of shocks.

What is claimed is:

1. A loom shuttle comprising, in combination, a shuttle body; a bobbin holder mounted in said shuttle body, said bobbin holder comprising a substantially rigid cover plate, a gripper spring, and a member of resilient material located between said cover plate and said gripper spring and connecting said cover plate and said gripper spring so as to form one unit with the same while permitting said gripper spring to resiliently yield in all directions with respect to said cover plate; and fastening means for fastening said unit to said shuttle body, said fastening means being spaced from said gripper spring so as not to hamper yielding movement of the latter relative to said cover plate.

2. A loom shuttle as set forth in claim 1, said gripper spring being U-shaped in cross-section.

3. A loom shuttle as set forth in claim 1, said cover plate defining together with the gripper-spring a substantially enclosed space within the loom shuttle body, said member being accommodated in said space and within said loom shuttle body, said space being enclosed by a circumferential wall and said cover plate having a pair of limbs provided with respective end faces which freely protrude toward said wall, the end faces of said limbs bearing on the gripper spring, said limbs further comprising respective surface layers disposed between said end faces and the gripper spring for joining said member and said gripper spring.

4. A loom shuttle as set forth in claim 1, wherein said member of resilient material further comprises surface layers engaging limbs of said cover plate, said limbs of said cover plate extending parallel to a bottom portion of the loom shuttle and said surface layers being adapted to connect said member and said gripper spring into a unit.

5. A loom shuttle as set forth in claim 1, said cover plate defining together with the gripper-spring a substantially enclosed space within the loom shuttle body, said member being accommodated within said loom shuttle body, said space being enclosed by a circumferential wall and said member having a pair of limbs provided with respective end faces which freely protrude toward said wall, the end faces of said limbs bearing on the gripper spring, said limbs further comprising respective surface layers disposed between said end faces and the gripper spring for joining said member and said gripper spring, respective surface layers of said member engaging said limbs of said cover plate, said limbs of the cover plate extending parallel to a bottom portion of the loom shuttle and said surface layers being adapted to connect said cover plate and said gripper-spring into a unit.

6. A loom shuttle as set forth in claim 1, said cover plate having limbs extending parallel to a bottom portion of the loom shuttle body, said loom shuttle further comprising a spacer bushing extending between said limbs, said limbs having respective confronting inner boundary surfaces spaced apart by a given distance, said given distance and the length of the spacer tube both exceeding the height of the gripper spring, the member of resilient material being disposed in and filling the space between said limbs of the cover plate.

7. A loom shuttle as set forth in claim 1, said cover I plate having limbs extending parallel to a bottom portion of the loom shuttle body, said loom shuttle further comprising a spacer bushing extending between said limbs, said limbs having respective confronting inner boundary surfaces spaced apart by a given distance, said given distance and the length of the spacer tube both exceeding the height of the gripper spring, the member of resilient material being disposed in and filling the space between said limbs of the cover plate, said member comprising a pair of portions provided with respective end faces freely protruding beyond the cover plate toward side walls of the loom shuttle, said end faces abutting respective limbs of a gripper-spring of U-shaped crosssection.

8. A loom shuttle as set forth in claim 1, said gripper spring being U-shaped in cross-section, and comprising a pair of parallel limbs having respective confronting surfaces, and bodies of resilient material carried on said confronting surfaces for engaging a bobbin-carrying spindle therebetween.

9. A loom shuttle comprising, in combination, a shuttle body; a bobbin holder mounted in said shuttle body, said bobbin holder comprising a substantially rigid U-shaped cover plate having a pair of spaced substantially parallel leg portions and a connecting portion connecting said leg portions at one end thereof, a U-shaped gripper spring having a pair of spring arms and a bent portion connecting said spring arms, said bent portion having a width smaller than the distance between said leg portions of said cover plate and said bent portion extending transversely through the space between said leg portions spaced from said connecting portion and opposite edge faces of said bent portion being spaced from opposite inner faces of said leg portions, said spring arms extending beyond said connection portion, and a body of resilient material filling the space between said bent portion and said connecting portion and said opposite inner faces of said leg portions and portions of said body filling the spaces between said edge faces of said bent portion and said inner faces of said leg portions so that said cover plate and said gripper spring form a unit with said body of resilient material 13 while said gripper spring may resiliently yield in all directions with respect to said cover plate; and fastening means for fastening said unit to said shuttle body, said fastening means being spaced from said gripper spring so as not to hamper yielding movement of the latter relative to said cover plate.

10. A loom shuttle as set forth in claim 9, wherein said body of resilient material is bonded at faces thereof engaging said gripper spring to the latter.

11. A loom shuttle as set forth in claim 9 wherein said body of resilient material is formed from rubber and vulcanized at faces thereof engaging said gripper spring to the latter.

12. A loom shuttle as set forth in claim 9, and including layers of resilient material sandwiched between outer faces of said leg portions and said shuttle body.

13. A loom shuttle as set forth in claim 9, wherein said leg portions are formed with aligned openings and said body with a bore therethrough aligned with said openings and wherein said fastening means includes a bolt extending through said openings and said bore and being fastened at one end thereof to said shuttle body.

14. A loom shuttle as set forth in claim 13, wherein said bore has a greater diameter than said openings and including a spacer bushing arranged about said bolt between said leg portions and engaging with opposite ends thereof said inner faces of said leg portions.

References Cited by the Examiner UNITED STATES PATENTS 1,132,664 3/1915 Mandeville 139-207 1,525,367 2/ 1925 Cadoret 139-207 2,100,688 11/1937 Douglas 139-207 2,138,221 11/1938 Turner 139-207 2,154,050 4/ 1939 Lundgren 139-207 2,205,025 6/ 1940 Balfour 139-196 2,270,821 1/ 1942 Kaufmann 139-207 2,282,191 5/1942 Kaufmann 139-196 2,748,807 6/1956 Kaufmann 139-196 3,048,197 8/1962 Fink 139-207 FOREIGN PATENTS 484,3 35 5 193 8 Great Britain. 630,716 10/1949 Great Britain.

DONALD W. PARKER, Primary Examiner.

H. S. JAUDON, Assistant Examiner. 

1. A LOOM SHUTTLE COMPRISING, IN COMBINATION, A SHUTTLE BODY; A BOBBIN HOLDER MOUNTED IN SAID SHUTTLE BODY, SAID BOBBIN HOLDER COMPRISING A SUBSTANTIALLY RIGID COVER PLATE, A GRIPPER SPRING, AND A MEMBER OF RESILIENT MATERIAL LOCATED BETWEEN SAID COVER PLATE AND SAID GRIPPER SPRING AND CONNECTING SAID COVER PLATE AND SAID GRIPPER SPRING SO AS TO FORM ONE UNIT WITH THE SAME WHILE PERMITTING SAID GRIPPER SPRING TO RESLIENTLY YIELD IN ALL DIRECTIONS WITH RESPECT TO SAID COVER PLATE; AND FASTENING MEANS FOR FASTENING SAID UNIT TO SAID SHUTTLE BODY, SAID FASTENING 